diff --git a/dist/browser/math-expression-evaluator.min.js b/dist/browser/math-expression-evaluator.min.js
index 63c3f9b..d6b0a01 100644
--- a/dist/browser/math-expression-evaluator.min.js
+++ b/dist/browser/math-expression-evaluator.min.js
@@ -1 +1 @@
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r=0;r<i[o].length;r++)if(e[a].token===i[o][r]){h=f(i[o][r],this.tokens);break}-1===h?(this.tokens.push(e[a]),e[a].precedence=n[e[a].type],i.length<=e[a].token.length&&(i[e[a].token.length]=[]),i[e[a].token.length].push(e[a].token)):(this.tokens[h]=e[a],e[a].precedence=n[e[a].type])}}function f(e,t){for(var n=0;n<t.length;n++)if(t[n].token===e)return n;return-1}var y=function(e,t){var n,v={value:this.math.changeSign,type:0,precedence:1,show:"-"},y={value:")",show:")",type:5,precedence:0},c={value:"(",type:4,precedence:0,show:"("},w=[c],m=[],E=e,g=o,N=0,d=u,A="";void 0!==t&&this.addToken(t);var k=function(e,t){for(var n,a,o,h=[],r=t.length,u=0;u<r;u++)if(!(u<r-1&&" "===t[u]&&" "===t[u+1])){for(n="",a=t.length-u>i.length-2?i.length-1:t.length-u;a>0;a--)if(void 0!==i[a])for(o=0;o<i[a].length;o++)l(t,i[a][o],u,a)&&(n=i[a][o],o=i[a].length,a=0);if(u+=n.length-1,""===n)throw new Error("Can't understand after "+t.slice(u));h.push(e.tokens[f(n,e.tokens)])}return h}(this,E);for(n=0;n<k.length;n++){var M=k[n];if(14!==M.type){var O,T=M.token,_=M.type,I=M.value,P=M.precedence,R=M.show,C=w[w.length-1];for(O=m.length;O--&&0===m[O];)if(-1!==[0,2,3,4,5,9,10,11,12,13].indexOf(_)){if(!0!==g[_])throw new Error(T+" is not allowed after "+A);w.push(y),g=h,d=s,m.pop()}if(!0!==g[_])throw new Error(T+" is not allowed after "+A);!0===d[_]&&(_=2,I=this.math.mul,R="&times;",P=3,n-=1);var S={value:I,type:_,precedence:P,show:R,numberOfArguments:M.numberOfArguments};if(0===_)g=o,d=u,a(m,2),w.push(S),4!==k[n+1].type&&(w.push(c),m.push(2));else if(1===_)1===C.type?(C.value+=I,a(m,1)):w.push(S),g=h,d=r;else if(2===_)g=o,d=u,a(m,2),w.push(S);else if(3===_)w.push(S),g=h,d=s;else if(4===_)a(m,1),N++,g=o,d=u,w.push(S);else if(5===_){if(!N)throw new Error("Closing parenthesis are more than opening one, wait What!!!");N--,g=h,d=s,w.push(S),a(m,1)}else if(6===_){if(C.hasDec)throw new Error("Two decimals are not allowed in one number");1!==C.type&&(C={show:"0",value:0,type:1,precedence:0},w.push(C)),g=p,a(m,1),d=u,C.value+=I,C.hasDec=!0}else 7===_&&(g=h,d=s,a(m,1),w.push(S));8===_?(g=o,d=u,a(m,M.numberOfArguments+2),w.push(S),4!==k[n+1].type&&(w.push(c),m.push(M.numberOfArguments+2))):9===_?(9===C.type?C.value===this.math.add?(C.value=I,C.show=R,a(m,1)):C.value===this.math.sub&&"-"===R&&(C.value=this.math.add,C.show="+",a(m,1)):5!==C.type&&7!==C.type&&1!==C.type&&3!==C.type&&13!==C.type?"-"===T&&(g=o,d=u,a(m,2).push(2),w.push(v),w.push(c)):(w.push(S),a(m,2)),g=o,d=u):10===_?(g=o,d=u,a(m,2),w.push(S)):11===_?(g=o,d=u,w.push(S)):12===_?(g=o,d=u,a(m,6),w.push(S),4!==k[n+1].type&&(w.push(c),m.push(6))):13===_&&(g=h,d=s,w.push(S)),a(m,-1),A=T}else if(n>0&&n<k.length-1&&1===k[n+1].type&&(1===k[n-1].type||6===k[n-1].type))throw new Error("Unexpected Space")}for(O=m.length;O--;)w.push(y);if(!0!==g[5])throw new Error("complete the expression");for(;N--;)w.push(y);return w.push(y),w};function c(e){for(var t,n,a,o=[],h=-1,r=-1,u=[{value:"(",type:4,precedence:0,show:"("}],s=1;s<e.length;s++)if(1===e[s].type||3===e[s].type||13===e[s].type)1===e[s].type&&(e[s].value=Number(e[s].value)),o.push(e[s]);else if(4===e[s].type)u.push(e[s]);else if(5===e[s].type)for(;4!==(null==(p=n=u.pop())?void 0:p.type);){var p;n&&o.push(n)}else if(11===e[s].type){for(;4!==(null==(i=n=u.pop())?void 0:i.type);){var i;n&&o.push(n)}u.push(n)}else{r=(t=e[s]).precedence,h=(a=u[u.length-1]).precedence;var l="Math.pow"==a.value&&"Math.pow"==t.value;if(r>h)u.push(t);else{for(;h>=r&&!l||l&&r<h;)n=u.pop(),a=u[u.length-1],n&&o.push(n),h=a.precedence,l="Math.pow"==t.value&&"Math.pow"==a.value;u.push(t)}}return o}function w(e,t){(t=t||{}).PI=Math.PI,t.E=Math.E;for(var n,a,o,h=[],r=void 0!==t.n,u=0;u<e.length;u++)if(1===e[u].type)h.push({value:e[u].value,type:1});else if(3===e[u].type)h.push({value:t[e[u].value],type:1});else if(0===e[u].type){var s=h[h.length-1];Array.isArray(s)?s.push(e[u]):s.value=e[u].value(s.value)}else if(7===e[u].type){var p=h[h.length-1];Array.isArray(p)?p.push(e[u]):p.value=e[u].value(p.value)}else if(8===e[u].type){for(var i=[],l=0;l<e[u].numberOfArguments;l++){var v=h.pop();v&&i.push(v.value)}h.push({type:1,value:e[u].value.apply(e[u],i.reverse())})}else if(10===e[u].type)n=h.pop(),a=h.pop(),Array.isArray(a)?((a=a.concat(n)).push(e[u]),h.push(a)):Array.isArray(n)?(n.unshift(a),n.push(e[u]),h.push(n)):h.push({type:1,value:e[u].value(a.value,n.value)});else if(2===e[u].type||9===e[u].type)n=h.pop(),a=h.pop(),Array.isArray(a)?((a=a.concat(n)).push(e[u]),h.push(a)):Array.isArray(n)?(n.unshift(a),n.push(e[u]),h.push(n)):h.push({type:1,value:e[u].value(a.value,n.value)});else if(12===e[u].type){n=h.pop();var f=void 0;f=!Array.isArray(n)&&n?[n]:n||[],a=h.pop(),o=h.pop(),h.push({type:1,value:e[u].value(o.value,a.value,f)})}else 13===e[u].type&&(r?h.push({value:t[e[u].value],type:3}):h.push([e[u]]));if(h.length>1)throw new Error("Uncaught Syntax error");return parseFloat(h[0].value.toFixed(15))}var m=function(){function t(){var t;this.toPostfix=c,this.addToken=v,this.lex=y,this.postfixEval=w,this.math=(t=this,{isDegree:!0,acos:function(e){return t.math.isDegree?180/Math.PI*Math.acos(e):Math.acos(e)},add:function(e,t){return e+t},asin:function(e){return t.math.isDegree?180/Math.PI*Math.asin(e):Math.asin(e)},atan:function(e){return t.math.isDegree?180/Math.PI*Math.atan(e):Math.atan(e)},acosh:function(e){return Math.log(e+Math.sqrt(e*e-1))},asinh:function(e){return Math.log(e+Math.sqrt(e*e+1))},atanh:function(e){return Math.log((1+e)/(1-e))},C:function(e,n){var a=1,o=e-n,h=n;h<o&&(h=o,o=n);for(var r=h+1;r<=e;r++)a*=r;var u=t.math.fact(o);return"NaN"===u?"NaN":a/u},changeSign:function(e){return-e},cos:function(e){return t.math.isDegree&&(e=t.math.toRadian(e)),Math.cos(e)},cosh:function(e){return(Math.pow(Math.E,e)+Math.pow(Math.E,-1*e))/2},div:function(e,t){return e/t},fact:function(e){if(e%1!=0)return"NaN";for(var t=1,n=2;n<=e;n++)t*=n;return t},inverse:function(e){return 1/e},log:function(e){return Math.log(e)/Math.log(10)},mod:function(e,t){return e%t},mul:function(e,t){return e*t},P:function(e,t){for(var n=1,a=Math.floor(e)-Math.floor(t)+1;a<=Math.floor(e);a++)n*=a;return n},Pi:function(e,n,a){for(var o=1,h=e;h<=n;h++)o*=Number(t.postfixEval(a,{n:h}));return o},pow10x:function(e){for(var t=1;e--;)t*=10;return t},sigma:function(e,n,a){for(var o=0,h=e;h<=n;h++)o+=Number(t.postfixEval(a,{n:h}));return o},sin:function(e){return t.math.isDegree&&(e=t.math.toRadian(e)),Math.sin(e)},sinh:function(e){return(Math.pow(Math.E,e)-Math.pow(Math.E,-1*e))/2},sub:function(e,t){return e-t},tan:function(e){return t.math.isDegree&&(e=t.math.toRadian(e)),Math.tan(e)},tanh:function(e){return t.math.sinh(e)/t.math.cosh(e)},toRadian:function(e){return e*Math.PI/180},and:function(e,t){return e&t}}),this.tokens=function(t){return[{token:"sin",show:"sin",type:0,value:t.math.sin},{token:"cos",show:"cos",type:0,value:t.math.cos},{token:"tan",show:"tan",type:0,value:t.math.tan},{token:"pi",show:"&pi;",type:3,value:"PI"},{token:"(",show:"(",type:4,value:"("},{token:")",show:")",type:5,value:")"},{token:"P",show:"P",type:10,value:t.math.P},{token:"C",show:"C",type:10,value:t.math.C},{token:" ",show:" ",type:14,value:" ".anchor},{token:"asin",show:"asin",type:0,value:t.math.asin},{token:"acos",show:"acos",type:0,value:t.math.acos},{token:"atan",show:"atan",type:0,value:t.math.atan},{token:"7",show:"7",type:1,value:"7"},{token:"8",show:"8",type:1,value:"8"},{token:"9",show:"9",type:1,value:"9"},{token:"int",show:"Int",type:0,value:Math.floor},{token:"cosh",show:"cosh",type:0,value:t.math.cosh},{token:"acosh",show:"acosh",type:0,value:t.math.acosh},{token:"ln",show:" ln",type:0,value:Math.log},{token:"^",show:"^",type:10,value:Math.pow},{token:"root",show:"root",type:0,value:Math.sqrt},{token:"4",show:"4",type:1,value:"4"},{token:"5",show:"5",type:1,value:"5"},{token:"6",show:"6",type:1,value:"6"},{token:"/",show:"&divide;",type:2,value:t.math.div},{token:"!",show:"!",type:7,value:t.math.fact},{token:"tanh",show:"tanh",type:0,value:t.math.tanh},{token:"atanh",show:"atanh",type:0,value:t.math.atanh},{token:"Mod",show:" Mod ",type:2,value:t.math.mod},{token:"1",show:"1",type:1,value:"1"},{token:"2",show:"2",type:1,value:"2"},{token:"3",show:"3",type:1,value:"3"},{token:"*",show:"&times;",type:2,value:t.math.mul},{token:"sinh",show:"sinh",type:0,value:t.math.sinh},{token:"asinh",show:"asinh",type:0,value:t.math.asinh},{token:"e",show:"e",type:3,value:"E"},{token:"log",show:" log",type:0,value:t.math.log},{token:"0",show:"0",type:1,value:"0"},{token:".",show:".",type:6,value:"."},{token:"+",show:"+",type:9,value:t.math.add},{token:"-",show:"-",type:9,value:t.math.sub},{token:",",show:",",type:11,value:","},{token:"Sigma",show:"&Sigma;",type:12,value:t.math.sigma},{token:"n",show:"n",type:13,value:"n"},{token:"Pi",show:"&Pi;",type:12,value:t.math.Pi},{token:"pow",show:"pow",type:8,value:Math.pow,numberOfArguments:2},{token:"&",show:"&",type:9,value:t.math.and}].map((function(t){return e({},t,{precedence:n[t.type]})}))}(this)}return t.prototype.eval=function(e,t,n){return this.postfixEval(this.toPostfix(this.lex(e,t)),n)},t}();return m.TOKEN_TYPES=t,m.tokenTypes=t,m}));
diff --git a/src/lexer.ts b/src/lexer.ts
index ff9b301..149dcc6 100644
--- a/src/lexer.ts
+++ b/src/lexer.ts
@@ -190,7 +190,7 @@ export const lex = function (this: Mexp, inp: string, tokens: Token[]) {
 	var changeSignObj: ParsedToken = {
 		value: this.math.changeSign,
 		type: 0,
-		precedence: 21,
+		precedence: 1,
 		show: '-',
 	}
 	var closingParObj: ParsedToken = {
diff --git a/test/index.js b/test/index.js
index 196dcef..2f4fa96 100644
--- a/test/index.js
+++ b/test/index.js
@@ -53,7 +53,7 @@ describe('Testing Unit', function () {
 		assert.equal(mexp.eval('2^5*2'), 64)
 	})
 	it('-3^2=9', function () {
-		assert.equal(mexp.eval('-3^2'), 9)
+		assert.equal(mexp.eval('-3^2'), -9)
 	})
 	it('3^2-2^2=5', function () {
 		assert.equal(mexp.eval('3^2-2^2'), 5)
diff --git a/test/single.js b/test/single.js
index a0707c5..1ba3eae 100644
--- a/test/single.js
+++ b/test/single.js
@@ -5,6 +5,6 @@ var Mexp = require('../dist/es/index.js')
 var mexp = new Mexp()
 describe('Testing Issue #64', function () {
 	it('should check parenthesis less number with exponent', function () {
-		assert.equal(mexp.eval('-3^(1+1)'), 9)
+		assert.equal(mexp.eval('-3^(1+1)'), -9)
 	})
 })