49 lines
969 B
C++
49 lines
969 B
C++
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/*
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* C++ Program to Implement Fermat's Little Theorem
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*/
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#include <iostream>
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using namespace std;
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/* calculates (a^b)%MOD */
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int pow(int a, int b, int MOD)
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{
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int x = 1, y = a;
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while (b > 0)
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{
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if (b % 2 == 1)
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{
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x = (x * y);
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if (x > MOD)
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x %= MOD;
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}
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y = (y * y);
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if (y > MOD)
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y %= MOD;
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b /= 2;
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}
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return x;
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}
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int modInverse(int a, int m)
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{
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return pow(a, m - 2, m);
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}
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//Main
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int main()
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{
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int a, m;
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cout<<"Enter number to find modular multiplicative inverse: ";
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cin>>a;
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cout<<"Enter Modular Value: ";
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cin>>m;
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cout<<modInverse(a, m)<<endl;
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}
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/*
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Enter number to find modular multiplicative inverse: 1111
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Enter Modular Value: 331
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216
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------------------
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(program exited with code: 1)
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Press return to continue
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