//  [javascript]
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"for (const i of (function*(to){if(to>=0){for(let i=0;i<to;i++)yield i;}else{for(let i=0; i>to;i--)yield i;}})(n)) {\n(() => {\nif ((b[i]>=a[i])) {\nc=(c+a[i]+Math.min(a[(i+1)],(b[i]-a[i])));\nreturn a[(i+1)]=Math.max(0,(a[(i+1)]-(b[i]-a[i])));\n} else {\nc=(c+b[i])\n;}\n;\n})()\n}";'let lines=input.split("\\n");\nlet l1=null;\nlet l2=null;\nlet l3=null;\nlet n=null;\nlet a=null;\nlet b=null;\nlet c=0;\n[l1, l2, l3]=input.split("\\n");\nn=parseInt(l1);\na=l2.split(" ").map((x) => {\nreturn parseInt(x);\n});\nb=l3.split(" ").map((x) => {\nreturn parseInt(x);\n});\n(() => {\nfor (const i of (function*(to){if(to>=0){for(let i=0;i<to;i++)yield i;}else{for(let i=0; i>to;i--)yield i;}})(n)) {\n(() => {\nif ((b[i]>=a[i])) {\nc=(c+a[i]+Math.min(a[(i+1)],(b[i]-a[i])));\nreturn a[(i+1)]=Math.max(0,(a[(i+1)]-(b[i]-a[i])));\n} else {\nc=(c+b[i])\n;}\n;\n})()\n};\n})();\nreturn console.log(c)';
function main(a){return function(){a.split("\n");var b=null,c=null,d=null,g=null,e=null,f=null,h=0;d=$jscomp.makeIterator(a.split("\n"));b=d.next().value;c=d.next().value;d=d.next().value;g=parseInt(b);e=c.split(" ").map(function(a){return parseInt(a)});f=d.split(" ").map(function(a){return parseInt(a)});(function(){for(var a={},b=$jscomp.makeIterator(function k(a){var b,c;return $jscomp.generator.createGenerator(k,function(d){switch(d.nextAddress){case 1:if(0<=a){d.jumpTo(2);break}b=0;case 4:if(!(b>
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