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Curve25519 library for Java

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package org.whispersystems.curve25519.java;

public class fe_cswap {

//CONVERT #include 
//CONVERT #include "fe.h"

/*
Replace (f,g) with (g,f) if b == 1;
replace (f,g) with (f,g) if b == 0.

Preconditions: b in {0,1}.
*/

    public static void fe_cswap(int[] f, int[] g, int b) {
        int f0 = f[0];
        int f1 = f[1];
        int f2 = f[2];
        int f3 = f[3];
        int f4 = f[4];
        int f5 = f[5];
        int f6 = f[6];
        int f7 = f[7];
        int f8 = f[8];
        int f9 = f[9];
        int g0 = g[0];
        int g1 = g[1];
        int g2 = g[2];
        int g3 = g[3];
        int g4 = g[4];
        int g5 = g[5];
        int g6 = g[6];
        int g7 = g[7];
        int g8 = g[8];
        int g9 = g[9];
        int x0 = f0 ^ g0;
        int x1 = f1 ^ g1;
        int x2 = f2 ^ g2;
        int x3 = f3 ^ g3;
        int x4 = f4 ^ g4;
        int x5 = f5 ^ g5;
        int x6 = f6 ^ g6;
        int x7 = f7 ^ g7;
        int x8 = f8 ^ g8;
        int x9 = f9 ^ g9;
        b = -b;
        x0 &= b;
        x1 &= b;
        x2 &= b;
        x3 &= b;
        x4 &= b;
        x5 &= b;
        x6 &= b;
        x7 &= b;
        x8 &= b;
        x9 &= b;
        f[0] = f0 ^ x0;
        f[1] = f1 ^ x1;
        f[2] = f2 ^ x2;
        f[3] = f3 ^ x3;
        f[4] = f4 ^ x4;
        f[5] = f5 ^ x5;
        f[6] = f6 ^ x6;
        f[7] = f7 ^ x7;
        f[8] = f8 ^ x8;
        f[9] = f9 ^ x9;
        g[0] = g0 ^ x0;
        g[1] = g1 ^ x1;
        g[2] = g2 ^ x2;
        g[3] = g3 ^ x3;
        g[4] = g4 ^ x4;
        g[5] = g5 ^ x5;
        g[6] = g6 ^ x6;
        g[7] = g7 ^ x7;
        g[8] = g8 ^ x8;
        g[9] = g9 ^ x9;
    }


}