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33 lines
617 B
33 lines
617 B
11 years ago
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#include "utilities.hpp"
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#include <limits>
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using namespace std;
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int divi(int x, int y){
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// clearly we don't want a division by zero
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if(!y) {
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if(x < 0) return numeric_limits<int>::min();
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if(x == 0) return 1;
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return numeric_limits<int>::max();
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}
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// in this situation there is a overflow which causes a SIGFPE
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if(x == numeric_limits<int>::min() && y == -1) {
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return numeric_limits<int>::max();
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}
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return x / y;
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}
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// exponentiation by squaring
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int powi(int base, int exp){
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if(exp < 0) return 0;
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int res = 1;
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while (exp) {
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if (exp & 1)
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res *= base;
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exp >>= 1;
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base *= base;
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}
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return res;
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}
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